Gas-regulator vent



Dec. 6, 1955 L. c. BIGGLE GAS-REGULATOR VENT Filed Sept.

3 nventor, Aaf/ydf [576@15 Gttornen 2,725,889 Patented Dec. 6, ,1955

2,725,889 GAS-REGULATOR VENT Laurence C. Biggie, Altadena, Calif., assigner to General Controls Co., Glendale, Calif., a corporation of California My present invention relates to fluid pressure regulators, and more particularly to those of the diaphragmoperated low-pressure type employed for controlling the pressure of gaseous fuel supplied to domestic burners.

To guard against the possibility of lire hazard which might result in the event of serious rupture of the diaphragm, it is customary to provide an enclosed space, or breathing chamber, at the outside of the diaphragm, and a vent leading from that space to a safe place such as the interior of a furnace. When circumstances are such that it is impracticable to extend the vent to a safe place, as in connection with cooking ranges or unvented heaters, it is usually permissible to restrict the vent so that fuel gas could escape only at low rate if the diaphragm were ruptured. However, such a restricted vent does not permit a rate of exchange of air between the breathing chamber and the atmosphere suicient for proper operative movements of the diaphragm, so that the regulating characteristics of the device are impaired.

It is an object of this invention to provide, in a regulator of the character described, means for limiting possible escape of fuel gas from the breathing chamber to a safe rate, without affecting the operating characteristics of the regulator.

Another object of the invention is to provide means for completely preventing escape of fuel gas from the breathing chamber in the event of rupture of the diaphragm, which means likewise does not interfere with the proper functioning of the regulator.

For full understanding of the invention, and further appreciation of its features and advantages, reference is to be had to the following detailed description and accompanying drawing, and to the appended claim.

In the drawing:

Figure 1 is a vertical sectional view, taken along the line lkl of Fig. 2, of a fluid pressure regulator embodying this invention; the parts being shown in the positions assumed in normal operation;

Figure 2 is a horizontal section taken generally along the line 2`2 of Fig. 1 and viewed in an upward direction; and

Figure 3 is a fragmentary detail showing a modified form of vent closure.

Referring first more particularly to Figs. l and 2 of the drawing, the numeral 11 indicates a casing having an inlet 12 and an outlet 13 separated by a generally rightangled partition 14. Mounted in an opening through the horizontal part of this partition is a cupped member 15 having in its bottom wall a port with which a tapered valve member 16 cooperates.

The open top of casing 11 is closed by a exible diaphragm 17, of material such as leather or synthetic rubber, which is clamped at its margin to the casing by the ange of a domed cover 18. Secured to the diaphragm is a stem 19 for the valve member 16; the stem being bolted to the diaphragm with a pair of stiifening plates 20 and 21 on 70 opposite sides of the diaphragm and a cupped washer 22 on top of the upper plate 20.

Biasing diaphragm 17 downward, and valve member 16 toward open position, is a compression spring 23whose bottom is within the cup of washer 22 and whose top bears against an adjusting screw 24 threaded in an opening through a thickened portion 25 of the top wall of K cover 18; this opening being sealed at its top by a cap screw 26. Beneath the diaphgram, and in the outlet chamberof the regulator, is a bae plate 27 which is apertured for stem 19 and has an opening wherein an aspirator tube 28 is mounted; the purpose of the baie plate being to prevent fluid entering the outlet from acting directly on the diaphragm.

The breathing chamber 29 defined by cover 18 and diaphragm 17 is provided with a vent 30 which communicates with the atmosphere by way of a cylindrical recess 31 in the cover portion 25; the recess 31 being provided with an apertured dust-cap 32 whose lingers 33 grip the side wall of the recess. Formed around the inner end of vent 30 is an annular knife-edged seat 34 with which a disk-shaped closure 35 cooperates. The closure 35 is preferably of soft material and is secured, as by cement, to one end portion 36 of a lever 37 whose other end portion 38 is bifurcated so as to straddle the cupped washer 22. The lever 37 is slit and deformed to provide a free opening near the middle of the lever for a pivot pin 39 which is clamped by a screw 40 in a V-groove (not shown) in a boss 41 on the underside of cover 18.

The bifurcated end portion 38 of the lever 37 is provided with weights 42 which so bias the lever that the tips of that portion rest on the diaphragm-plate 20; the lever being so bent that, when the regulator is in normal operportion of the lever is only just out of engagement with the diaphragm plate 20. Threaded on boss 43 is a sealing cap 45.

Normal operation of the regulator shown in Figs. l and 2 is conventional: upward pressure on the diaphragm assembly of fluid, such as fuel gas, in the outlet 13 maintaining the valve member 16 in a partly-open position determined by the force of spring 23 and the capacity of the burner being supplied.

In the event of rupture of the diaphragm the fluid pressures above and below it become equalized and the diaphragm assembly consequently falls, by gravity and under the force of spring 23, to a position wherein the bottom acting on it; the lever being free from the diaphragm assembly when the same reaches its limit of downward movement, as was mentioned above. The breathing chamber 29 is therefore effectively sealed from the atmosphere.

It will be observed that ow through the vent 30 is substantially unimpeded by the closure 35 in all normal operative positions of the diaphragm. After supply of gas has been shut-off ahead of the regulator and the diaphragm assembly is therefore in its lowermost position under the force of spring 23, upon resumption of the supply the vent closure is unseated when only slight initial movement of the diaphragm assembly occurs; such movement being permitted because of the elasticity of the air in the then-sealed breathing chamber. If means (such as screw 44) for accurately limiting the lowest position of the diaphragm assembly is not provided, the capacity of the'breathing chamber s'hould'be increased to avoid undue opposition to the upward j-movement of the diaphragm `before the Avent closure is unseated. Lever y37 is pivoted approximately at -its middle so that only slight initial movement Yof the lower end of thelever is required to effect substantial opening of the vent. It is to be observed that proper venting of the breathing chamber is not affected by surges of the diaphragm which may occur in normal operation of the regulator,

1f circumstances are such that complete sealing of the breathing chamber is not required in the event of rupture of the diaphragm, the -vent closure may be modified as shown in Fig. 3. YIn that figure the vent closure, indicated by the numeral 35', has a central opening 50 in register with another opening`51 in the lever portion 36. The opening 51 is so smallthat, if the diaphragm were ruptured, gas could escape from the breathing chamber only at low rate when the closure were seated as a result of the nipture, as was-described in connection with Figs. 1 and 2.

With the form of vent closure shown in Fig. 3 it is not necessary to limit downward movement of the diaphragm assembly to a position lwherein it is only just out of engagement with the lever, since, when the diaphragm starts its upward movement upon initial supply of gas to the regulator, air can escape from the breathing chamber through the opening in the vent closure.

The specific embodiment of my invention herein shown and described is obviously susceptible of modification without departing from the spirit of the invention, and 1 intend therefore to be limited only by the scope of the appended claim.

I claim as my invention:

In a uid pressure regulator of the type which comprises a flexible diaphragm subjected on one side to the pressure of the uid in the outlet of the regulator, means Vbiasing said diaphragm in a direction'opposng'said'pressure, means defining with the other side of the diaphragm a breathing chamber having a vent leading to the atmosphere, and a valve for closing said vent in the event of rupture of the diaphragm and having an operative connection with the diaphragm arranged so that the valve is maintained in open position during normal operation of the regulator and is closed only when the diaphragm is adjacent its ultimate biased position: the improvement consisting in that said vent is of such large ow capacity that operative movement of the diaphragm is unimpeded; and said valve comprises means forming a valve seat around the end of the vent facing inside said breathing chamber, a lever rockably mounted intermediate its ends within the breathing chamber, and a closure carried by one end of said lever and operatively engageable with said vent seat, said lever being arranged so that its other end engages vsaid diaphragm and the lever follows the movements of the diaphragm; the arrangement being such that movement of the diaphragm under the force of said biasing means elects movement of said closure toward seating position, and such that the closure is so spaced from its seat while the regulator is in normal operation that the flow capacity of the vent valve is then at least as great as that of the vent.

References Cited in the le of this patent UNITED STATES PATENTS 

